›› 2010, Vol. 53 ›› Issue (5): 479-486.doi:

• 研究论文 •    下一篇

家蚕幼虫不同龄期体内主要解毒酶及其基因表达的性别差异

刘海涛,李兵,赵国栋,张婷,高瑞娜,卫正国,沈卫德   

  • 出版日期:2010-05-20 发布日期:2010-05-20
  • 通讯作者: 沈卫德

Sexual differences in main detoxification enzymes and their gene expression in different instars of Bombyx mori larvae

LIU Hai-Tao, LI Bing, ZHAO Guo-Dong, ZHANG Ting, GAO Rui-Na, WEI Zheng-Guo, SHEN Wei-De   

  • Online:2010-05-20 Published:2010-05-20

摘要: 为了研究家蚕Bombyx mori性别与抗性的关系,本研究采用Thermo酶活性测定法和实时荧光定量PCR法,比较不同龄期雌雄家蚕起蚕体内解毒酶活性及其基因的表达差异。结果表明:解毒酶及其基因在雌雄个体之间均存在明显差异,谷胱甘肽S-转移酶活性及其基因BmGSTe5的表达量在1~3龄表现为雌蚕高于雄蚕,4龄和5龄则表现相反,其中4龄雄蚕酶活性和基因表达量分别是雌蚕的3.65倍和5.11倍,推测与雄蚕精巢在4龄初迅速发育有关。雄蚕乙酰胆碱酯酶活性在2~4龄分别是雌蚕的1.48,1.34和1.40倍;乙酰胆碱酯酶基因Bm-ace1在2龄和3龄性别差异不明显,Bm-ace2在2~4龄为雄性高于雌性,雄性分别是雌性的1.75,2.17和2.40倍,提示Bm-ace2对性别间该酶活性的差异影响较大。羧酸酯酶活性在2龄和3龄雄蚕较高,分别是雌蚕的1.23和1.87倍,4~5龄雌蚕较高,分别是雄蚕的1.23和1.22倍;羧酸酯酶基因BmCarE-5和BmCarE-10在性别间的差异规律均与酶活性相反,即羧酸酯酶表现为较高的基因表达量对应较低的酶活性,推测在家蚕体内可能存在“羧酸酯酶突变”现象。结果为研究基因表达产物的修饰方式及其功能开辟了新的研究路径,为家蚕性别与抗药性的研究提供了重要参考。

关键词: 家蚕, 性别, 抗性, 解毒酶, 基因表达, 酶活性

Abstract: In order to study the relationship between resistance and sex in male and female Bombyx mori, Thermo enzyme activity measurement and Real Time fluorescent quantitative RT-PCR were performed to compare differences of the activities of detoxification enzymes in male and female B. mori larvae and their genetic expression of newly exuviated larvae at different instars. The research demonstrated significant differences in detoxification enzymes and their related genes existed between male and female B mori larvae. The activities of glutathione S-transferases(GSTs)and BmGSTe5 showed higher expression in males than those in 1st-3rd instar females, while the opposite phenomena were found in 4th and 5th instar larvae. The ratios of enzyme activity and gene expression in the male and the female were 3.65 and 5.11, respectively, which were attributed to the fast development of testis in 4th instar larvae. The enzyme activities of acetylcholine esterase(AchE) in the male were 1.48,1.34 and 1.40 times compared to those of the female from 2nd to 4th instars, while its gene Bm-ace1 showed insignificant differences between male and female B. mori at 2nd and 3rd instars. The expression amount of gene Bm-ace2 in the male were 1.75,2.17 and 2.40 times as high as that in the female from 2nd to 4th instars, suggesting that Bm-ace2 plays a more important role in sex differences. The enzyme activities of carboxylesterase (CarE) in male were 1.23 and 1.87 times compared to that in female at 2nd and 3rd instars, and the activity ratios in the female and the male were 1.22 and 1.23 at 4th and 5th instars, respectively. The expression of BmCarE-5 and BmCarE-10 showed the opposite trend to enzyme activities between different sexes, i.e., lowlevel gene expression and high carboxylesterase activity. We so speculate that carboxylesterase mutation phenomenon exists in B.mori. These results break a new road for research on modification of genetic expression products and their function, and make further contribution to the study of relations between the gender and the ability of drug resistence in B. mori. 27 Refs. In Chinese.  

Key words: Bombyx mori, sex, resistance, detoxification enzyme, gene expression, enzyme activity